view release on metacpan or  search on metacpan

lib/LaTeXML/Post/LaTeXImages.pm  view on Meta::CPAN

  if (($$self{imagetype} eq 'svg') && (!defined $options{use_dvisvgm}) && which('dvisvgm')) {
    $$self{use_dvisvgm} = 1; }
  elsif ($$self{use_dvisvgm} && (($$self{imagetype} ne 'svg') || !which('dvisvgm'))) {
    $$self{use_dvisvgm} = 0; }    # but disable if inappropriate or unavailable
      # We'll use dvipng (MUCH faster) if requested or not forbidden & available.
      # But be careful: it can't handle much postscript, so better NOT for graphics!
  if (($$self{imagetype} eq 'png') && (!defined $options{use_dvipng}) && which('dvipng')) {
    $$self{use_dvipng} = 1; }
  elsif ($$self{use_dvipng} && (($$self{imagetype} ne 'png') || !which('dvipng'))) {
    $$self{use_dvipng} = 0; }    # but disable if inappropriate or unavailable.

  # Parameterize according to the selected dvi-to-whatever processor.
  my $mag = int($$self{magnification} * 1000);
  my $dpi = int($$self{DPI} * $$self{magnification});
  # Unfortunately, each command has incompatible -o option to name the output file.
  # Note that the formatting char used, '%', has to be doubled on Windows!!
  # Maybe that's only true when it looks like an environment variable?
  # Ie. %variable% ?
  #  my $fmt = ($^O eq 'MSWin32' ? '%%' : '%');
  my $fmt = '%';
  if ($$self{use_dvisvgm}) {
    ##    $$self{dvicmd}             = "dvisvgm --page=1- --bbox=min --mag=$mag -o imgx-${fmt}p";
    # dvisvgm currently creates glyph descriptions w/ unicode attribute having the wrong codepoint
    # firefox, chromium use this codepoint instead of the glyph "drawing"
    # a later version of dvisvgm should do better at synthesizing the unicode?
    # but for now, we'll use --no-fonts, which creates glyph drawings rather than "glyphs"
    # Also, increase the bounding box from min by 1pt
    $$self{dvicmd} = "dvisvgm --page=1- --bbox=1pt --scale=$$self{magnification} --no-fonts -o imgx-${fmt}3p";
    $$self{dvicmd_output_name} = 'imgx-%03d.svg';
    $$self{dvicmd_output_type} = 'svg';
    $$self{frame_output}       = 0; }
  elsif ($$self{use_dvipng}) {
    $$self{dvicmd}             = "dvipng -bg Transparent -T tight -q -D$dpi -o imgx-${fmt}03d.png";
    $$self{dvicmd_output_name} = 'imgx-%03d.png';
    $$self{dvicmd_output_type} = 'png32';
    $$self{frame_output}       = 1; }
  else {
    # Useful DVIPS options:
    #  -q  : run quietly
    #  -x#  : magnification * 1000
    #  -S1 -i  : make a separate file for each `section' consisting of a single page.
    #       QUESTION: dvips' naming scheme allows for 999 pages... what happens at 1000?
    #  -E   :  crop each page close to the `ink'.
    #  -j0  : don't subset fonts; silly really, but some font tests are making problems!
    $$self{dvicmd}             = "dvips -q -S1 -i -E -j0 -x$mag -o imgx";
    $$self{dvicmd_output_name} = 'imgx%03d';
    $$self{dvicmd_output_type} = 'eps';
    $$self{frame_output}       = 1; }
  return $self; }

#**********************************************************************
# Check whether this processor actually has the resources it needs to process.
# I don't know if there's a general API implied here;
# It could, conceivably be use in planning post processing?
# But generally, before signalling an error, you'd want to know that the processor
# is even needed.
# This test is called once we know that, from within
#
# At any rate: To process LaTeX snippets into images, we will need
#  * latex (or related) from a TeX installation
#  * Image::Magick (or similar) [see LaTeXML::Util::Image]
sub canProcess {
  my ($self) = @_;
  # Check if we have Image::Magick (or similar)
  if (!image_can_image()) {
    Error('expected', 'Image::Magick', undef,
      "No available image processing module found; Skipping.",
      "Please install one of: " . join(',', image_classes()));
    return; }
  # AND check if we have an approriprate latex!!!
  if (($LATEXCMD =~ /^(\S+)/) && !which($1)) {    # does the command seem to be available?
    Error('expected', $LATEXCMD, undef,
      "No latex command ($LATEXCMD) found; Skipping.",
      "Please install TeX to generate images from LaTeX");
    return; }
  return 1; }

#**********************************************************************
# Methods that must be defined;

# This is an abstract class; concrete classes must select the nodes to process.
# We'll still need to use $proc->extractTeX($doc,$node)
#  to extract the actual TeX string!
sub toProcess {
  return (); }

# $self->extractTeX($doc,$node)=>$texstring;
sub extractTeX {
  return ""; }

# $self->format_tex($texstring)
sub format_tex {
  return ""; }

# $self->setTeXImage($doc,$node,$imagepath,$width,$height);
# This is the default
sub setTeXImage {
  my ($self, $doc, $node, $path, $width, $height, $depth) = @_;
  $node->setAttribute('imagesrc',    pathname_to_url($path));
  $node->setAttribute('imagewidth',  $width);
  $node->setAttribute('imageheight', $height);
  $node->setAttribute('imagedepth',  $depth) if defined $depth;
  return; }

#======================================================================
# Methods that could be wrapped, overridden.

# Should be called by extractTeX
sub cleanTeX {
  my ($self, $tex) = @_;
  return unless defined $tex;
  my $style = '';
  # Save any leading style
  if ($tex =~ s/^\s*(\\displaystyle|\\textstyle|\\scriptstyle|\\scriptscriptstyle)\s*//) {
    $style = $1; }
  $tex =~ s/^(?:\\\s*,|\\!\s*|\\>\s*|\\;\s*|\\:\s*|\\ \s*|\\\/\s*)*//; # Trim leading spacing (especially negative!)
  $tex =~ s/(?:\\\s*,|\\!\s*|\\>\s*|\\;\s*|\\:\s*|\\ \s*|\\\/\s*)*$//;    # and trailing spacing
      # Strip comments, but watchout for \% (or more exactly, an ODD number of \)
  $tex =~ s/(?<!\\)((?:\\\\)*)\%[^\n]*\n/$1/gs;
  $tex = $style . ' ' . $tex if $style;    # Put back the style, if any
  return $tex; }

#**********************************************************************

#**********************************************************************
# Generating & Processing the LaTeX source.